Several cancer screening studies and projects are underway or being designed to gain a better understanding of the impact and consequences of such screening in various population settings. Staff are involved in the International Prostate Screening Trials Evaluation Group, an international collaboration for the evaluation of prostate cancer screening trials. Trial investigators from Europe and North America are involved in an effort to develop a common core protocol and database so that in future years, data from various trials can be effectively combined to provide a comprehensive evaluation of prostate cancer screening. Discussions centered on comparison of design features among the trials as well as a description of baseline data and initial PSA results. Staff are involved in international deliberations on the evaluation of screening for colorectal and ovarian cancers. Trial investigators from the U.S. and the United Kingdom have met to discuss common protocol and database features of their trials. It is hoped this will lead to enhanced design modification of new and ongoing trials and ultimately provide a common database so that in future years, data from various trials can be effectively combined to provide a more comprehensive evaluation of screening for these cancers than could be achieved by any single trial. Staff participate on the Data Safety and Monitoring Committee of the Prostate Cancer Prevention Trial which is carried out by the Southwest Oncology Group through funding from DCPC.